Provides guest Linux kernel module "qemu-hypertrace.ko" to abstract access to the hypertrace channel.
Signed-off-by: Lluís Vilanova <vilan...@ac.upc.edu> --- Makefile | 4 - configure | 4 + hypertrace/guest/linux-module/Kbuild.in | 5 + hypertrace/guest/linux-module/Makefile | 24 ++++ .../include/linux/qemu-hypertrace-internal.h | 46 +++++++ .../linux-module/include/linux/qemu-hypertrace.h | 71 +++++++++++ hypertrace/guest/linux-module/qemu-hypertrace.c | 133 ++++++++++++++++++++ 7 files changed, 286 insertions(+), 1 deletion(-) create mode 100644 hypertrace/guest/linux-module/Kbuild.in create mode 100644 hypertrace/guest/linux-module/Makefile create mode 100644 hypertrace/guest/linux-module/include/linux/qemu-hypertrace-internal.h create mode 100644 hypertrace/guest/linux-module/include/linux/qemu-hypertrace.h create mode 100644 hypertrace/guest/linux-module/qemu-hypertrace.c diff --git a/Makefile b/Makefile index bebd6e6..26fb418 100644 --- a/Makefile +++ b/Makefile @@ -460,8 +460,10 @@ endif endif install-hypertrace: - $(INSTALL_DIR) "$(DESTDIR)$(includedir)" + $(INSTALL_DIR) "$(DESTDIR)$(includedir)/linux" $(INSTALL_DATA) "$(SRC_PATH)/hypertrace/guest/user/qemu-hypertrace.h" "$(DESTDIR)$(includedir)/" + $(INSTALL_DATA) "$(SRC_PATH)/hypertrace/guest/linux-module/include/linux/qemu-hypertrace.h" "$(DESTDIR)$(includedir)/linux" + $(INSTALL_DATA) "$(SRC_PATH)/hypertrace/guest/linux-module/include/linux/qemu-hypertrace-internal.h" "$(DESTDIR)$(includedir)/linux" install: all $(if $(BUILD_DOCS),install-doc) \ diff --git a/configure b/configure index 076eb8b..b809f69 100755 --- a/configure +++ b/configure @@ -5782,6 +5782,10 @@ fi symlink "$source_path/Makefile.target" "$target_dir/Makefile" mkdir -p $target_dir/hypertrace/guest/user symlink $source_path/hypertrace/guest/user/Makefile $target_dir/hypertrace/guest/user/Makefile +if test "$target_softmmu" = "yes"; then + mkdir -p $target_dir/hypertrace/guest/linux-module + symlink $source_path/hypertrace/guest/linux-module/Makefile $target_dir/hypertrace/guest/linux-module/Makefile +fi upper() { echo "$@"| LC_ALL=C tr '[a-z]' '[A-Z]' diff --git a/hypertrace/guest/linux-module/Kbuild.in b/hypertrace/guest/linux-module/Kbuild.in new file mode 100644 index 0000000..87656d4 --- /dev/null +++ b/hypertrace/guest/linux-module/Kbuild.in @@ -0,0 +1,5 @@ +# -*- mode: makefile -*- + +src = $(MOD_SRC_PATH) +ccflags-y := -I$(src)/include/ -DHYPERTRACE_NUM_ARGS=$(HYPERTRACE_NUM_ARGS) +obj-m := qemu-hypertrace.o diff --git a/hypertrace/guest/linux-module/Makefile b/hypertrace/guest/linux-module/Makefile new file mode 100644 index 0000000..d9247a0 --- /dev/null +++ b/hypertrace/guest/linux-module/Makefile @@ -0,0 +1,24 @@ +include ../../../../config-host.mak +include ../../../config-target.mak +include $(SRC_PATH)/rules.mak + +MOD_SRC_PATH = $(SRC_PATH)/hypertrace/guest/linux-module + +LINUX_BUILD_PATH = /lib/modules/$(shell uname -r)/build + +vpath % $(MOD_SRC_PATH) + + +all: Kbuild + $(MAKE) -C $(LINUX_BUILD_PATH) M=$(shell pwd) \ + MOD_SRC_PATH=$(MOD_SRC_PATH) \ + HYPERTRACE_NUM_ARGS=$(CONFIG_HYPERTRACE_ARGS) \ + modules + +clean: Kbuild + $(MAKE) -C $(LINUX_BUILD_PATH) M=$(shell pwd) clean + rm -f $< + +Kbuild: $(MOD_SRC_PATH)/Kbuild.in Makefile + rm -f $@ + cp $< $@ diff --git a/hypertrace/guest/linux-module/include/linux/qemu-hypertrace-internal.h b/hypertrace/guest/linux-module/include/linux/qemu-hypertrace-internal.h new file mode 100644 index 0000000..465c003 --- /dev/null +++ b/hypertrace/guest/linux-module/include/linux/qemu-hypertrace-internal.h @@ -0,0 +1,46 @@ +/* -*- C -*- + * + * Guest-side management of hypertrace. + * + * Copyright (C) 2016 Lluís Vilanova <vilan...@ac.upc.edu> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, either version 3 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see http://www.gnu.org/licenses/. + */ + +extern uint64_t _qemu_hypertrace_channel_num_args; +extern uint64_t _qemu_hypertrace_channel_max_offset; +extern uint64_t *_qemu_hypertrace_channel_data; +extern uint64_t *_qemu_hypertrace_channel_control; + +static inline uint64_t qemu_hypertrace_num_args(void) +{ + return _qemu_hypertrace_channel_num_args; +} + +static inline uint64_t qemu_hypertrace_max_offset(void) +{ + return _qemu_hypertrace_channel_max_offset; +} + +static inline uint64_t *qemu_hypertrace_data(uint64_t data_offset) +{ + size_t args_size = qemu_hypertrace_num_args() * sizeof(uint64_t); + return &_qemu_hypertrace_channel_data[data_offset * args_size]; +} + +static inline void qemu_hypertrace (uint64_t data_offset) +{ + uint64_t *ctrlp = _qemu_hypertrace_channel_control; + ctrlp[1] = data_offset; +} diff --git a/hypertrace/guest/linux-module/include/linux/qemu-hypertrace.h b/hypertrace/guest/linux-module/include/linux/qemu-hypertrace.h new file mode 100644 index 0000000..bb6ad7f --- /dev/null +++ b/hypertrace/guest/linux-module/include/linux/qemu-hypertrace.h @@ -0,0 +1,71 @@ +/* -*- C -*- + * + * Guest-side management of hypertrace. + * + * Copyright (C) 2016 Lluís Vilanova <vilan...@ac.upc.edu> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, either version 3 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see http://www.gnu.org/licenses/. + */ + +#ifndef QEMU_HYPERTRACE_H +#define QEMU_HYPERTRACE_H + +#include <linux/types.h> + + +/** + * qemu_hypertrace_num_args: + * + * Number of uint64_t values read by each call to qemu_hypertrace(). + */ +static uint64_t qemu_hypertrace_num_args(void); + +/** + * qemu_hypertrace_data_size: + * + * Maximum data offset value accepted by other calls. + */ +static uint64_t qemu_hypertrace_max_offset(void); + +/** + * qemu_hypertrace_data: + * @data_offset: Offset in multiples of argument packs. + * + * Pointer to the start of the data channel. + */ +static uint64_t *qemu_hypertrace_data(uint64_t data_offset); + +/** + * qemu_hypertrace: + * @data_offset: Offset in multiples of argument packs. + * + * Invoke the control channel. + * + * Each of the users (e.g., CPU) of the hypertrace channel can use a different + * data offset to ensure they can work concurrently without using locks (i.e., + * each uses a different portion of the data channel). + * + * Note: You should use wmb() before writing into the control channel iff you + * have written into the data channel. + * + * Note: Use preempt_disable() and preempt_enable() if you're using data offsets + * based on the CPU identifiers (or else data might be mixed if a task is + * re-scheduled). + */ +static void qemu_hypertrace(uint64_t data_offset); + + +#include <linux/qemu-hypertrace-internal.h> + +#endif /* QEMU_HYPERTRACE_H */ diff --git a/hypertrace/guest/linux-module/qemu-hypertrace.c b/hypertrace/guest/linux-module/qemu-hypertrace.c new file mode 100644 index 0000000..43d35d7 --- /dev/null +++ b/hypertrace/guest/linux-module/qemu-hypertrace.c @@ -0,0 +1,133 @@ +/* + * Guest-side management of hypertrace. + * + * Copyright (C) 2016 Lluís Vilanova <vilan...@ac.upc.edu> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, either version 3 of the + * License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see http://www.gnu.org/licenses/. + */ + +#include <linux/qemu-hypertrace.h> + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/uaccess.h> + + +#define VERSION_STR "0.1" +#define PCI_VENDOR_ID_REDHAT_QUMRANET 0x1af4 +#define PCI_DEVICE_ID_HYPERTRACE 0x10f0 + + +MODULE_DESCRIPTION("Kernel interface to QEMU's hypertrace device"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Lluís Vilanova"); +MODULE_VERSION(VERSION_STR); + + +////////////////////////////////////////////////////////////////////// +// Kernel interface + +uint64_t _qemu_hypertrace_channel_num_args = HYPERTRACE_NUM_ARGS; +uint64_t _qemu_hypertrace_channel_max_offset = 0; +uint64_t *_qemu_hypertrace_channel_control = NULL; +uint64_t *_qemu_hypertrace_channel_data = NULL; + +EXPORT_SYMBOL(_qemu_hypertrace_channel_num_args); +EXPORT_SYMBOL(_qemu_hypertrace_channel_max_offset); +EXPORT_SYMBOL(_qemu_hypertrace_channel_data); +EXPORT_SYMBOL(_qemu_hypertrace_channel_control); + + +////////////////////////////////////////////////////////////////////// +// Channel initialization + +static +int +init_channel (uint64_t **vaddr, struct pci_dev *dev, int bar) +{ + void * res; + resource_size_t start, size; + + start = pci_resource_start(dev, bar); + size = pci_resource_len(dev, bar); + + if (start == 0 || size == 0) { + return -ENOENT; + } + + res = ioremap(start, size); + if (res == 0) { + return -EINVAL; + } + + *vaddr = res; + return 0; +} + +////////////////////////////////////////////////////////////////////// +// Module (de)initialization + +int init_module(void) +{ + int res = 0; + struct pci_dev *dev = NULL; + size_t args_size; + size_t data_size; + + printk(KERN_NOTICE "Loading QEMU hypertrace module (version %s)\n", + VERSION_STR); + + dev = pci_get_device(PCI_VENDOR_ID_REDHAT_QUMRANET, PCI_DEVICE_ID_HYPERTRACE, NULL); + if (dev == NULL) { + res = -ENOENT; + printk(KERN_ERR "Unable to find hypertrace device\n"); + goto error; + } + + res = init_channel(&_qemu_hypertrace_channel_control, dev, 0); + if (res != 0) { + printk(KERN_ERR "Unable to find hypertrace control channel\n"); + goto error; + } + + res = init_channel(&_qemu_hypertrace_channel_data, dev, 1); + if (res != 0) { + printk(KERN_ERR "Unable to find hypertrace data channel\n"); + goto error_data; + } + + args_size = _qemu_hypertrace_channel_num_args * sizeof(uint64_t); + data_size = pci_resource_len(dev, 1); + _qemu_hypertrace_channel_max_offset = data_size / args_size; + + goto ok; + +error_data: + iounmap(_qemu_hypertrace_channel_control); + +error: + _qemu_hypertrace_channel_control = NULL; + _qemu_hypertrace_channel_data = NULL; + +ok: + return res; +} + +void cleanup_module(void) +{ + printk(KERN_NOTICE "Unloading QEMU hypertrace module\n"); + + iounmap(_qemu_hypertrace_channel_control); + iounmap(_qemu_hypertrace_channel_data); +}